(1) Field of the Invention
The present invention relates to a content distribution system that accepts a user request via a network such as the Internet, splices a plurality of pieces of stream data into a line of stream data based on the user request, and distributes the line of stream data to the user terminal. More specifically, the present invention relates to a stream data splicing processing.
(2) Description of the Prior Art
In recent years, services for distributing users with multimedia contents (hereinafter referred to as contents) that include commercial messages (CMs) of sponsors of the contents at no extra charge have been offered. In order to meet users' higher demands in free distribution of the contents, much attention has been paid to the research and development of a content distribution system for arranging a content according to a user's request and distributing the content to the user.
According to conventional television and radio broadcasting, broadcasting service providers determine where to insert the CMs according to the program structure and plot development. The above described content distribution system employs a method for automatically determining a position where a CM is to be inserted in the program.
An example of methods to determine the position where th CM is to be inserted in the program is disclosed in Japanese Patent No. 3315928 as a method for inserting the CM. According to the method for inserting the CM of Japanese Patent No. 3315928, information indicating a position where the CM insertion is recommended is included in program data in advance, the CM is inserted into a CM insertion recommended position on a time-line of a reproducing time indicated by the information, and then the program and the CM are spliced. In the above manner, it is possible to insert the CM automatically into the program at an appropriate position.
Even when the CM is inserted according to the above method, however, it is still probable that an abrupt switching to the CM from the program makes the user watching and listening to the program feel unpleasant or surprised because the program and the CM are completely different.